Lack of association between CYB5A gene rs1790834 polymorphism and the response to leflunomide in women with rheumatoid arthritis

Aim Leflunomide is a disease-modifying antirheumatic drug used in therapy for rheumatoid arthritis (RA). Previous studies indicated that oestrogens and androgens may affect the response to leflunomide in RA patients. The synthesis of androgens is regulated by cytochrome CYB5A. The aim of this study was to examine the association between the CYB5A gene rs1790834 polymorphism and the response to leflunomide in women with RA. Methods The study included 111 women diagnosed with RA. Leflunomide was administered in monotherapy at a dose of 20 mg/day. All patients underwent a monthly evaluation for 12 months after the initiation of treatment with leflunomide. Results After 12 months of therapy, the changes in individual disease activity parameters, such as: DAS28, ESR, CRP and VAS, were not statistically significantly different between rs1790834 genotypes in the Kruskal–Wallis test. Conclusions The results of our study suggest lack of statistically significant association between the CYB5A gene rs1790834 polymorphism and the response to leflunomide in women with RA.